PL122038B2 - Method of manufacture of microelement nutrients in complexed formenty, v kompleksnojj forme - Google Patents

Description

The subject of the invention is a method of producing micronutrient fertilizers complexed with polyphosphoric acids. In addition to nitrogen, phosphorus, potassium, calcium, magnesium and sulfur, plants require small amounts of other elements such as iron, copper, manganese, zinc, boron, molybdenum for proper development. , cobalt and others, commonly referred to as micronutrients. Agricultural studies have shown that in comparison with common salts of these elements (for example chlorides, sulphates, nitrates, borates, molybdates) the micronutrients in a complexed form show the most favorable effect. Among the various complexing agents, such as citric acid, tartaric acid, ethylenediamine-tetraacetic acid, polyphosphoric acids with up to several dozen chain-linked PO2 OH groups in the molecule have also been proposed for this purpose. The best known solution in this respect is the introduction of micronutrients into superphosphoric acid obtained from elemental phosphorus or by deep evaporation of extractive phosphoric acid, possibly in combination with its neutralization with ammonia. Such products in the form of solids or in the form of concentrated solutions contain a certain proportion of phosphates in the form of "poly", also generally called non-ortho forms, which have the property of forming soluble complexes with heavy metal cations, which allows the incorporation of micronutrient salts with complete clarity of the solutions. is that the pyrolytic condensation of orthophosphates to forms of abnormalities is favored by the presence of certain substances, which include, for example, urea. The action of urea can be explained simply by the fact that urea hydrolyzes at the expense of constitutional water contained in phosphate acid to ammonia and carbon dioxide. It is a particularly convenient starting material. urea phosphate with the formula CO / NH212 H3PO4, which is an additive compound of anhydrous phosphoric acid and urea, turned out to be urea phosphate for the preparation of polyphosphates. The method of producing micronutrient fertilizers in a complexed form according to the invention is characterized by the fact that it uses that the pyrolysis product of urea phosphate is heated to 140-220 ° C and the trace elements in the form of oxides or hydroxides or salts are added to the urea phosphate during pyrolysis or to the finished pyrolysis product or to the aqueous solution of the pyrolysis product. When urea is heated to about 120 ° C, it melts and begins to emit carbon dioxide and then ammonia. When a temperature of around 200 ° C is reached, the material takes the form of a white sintered powder. The urea phosphate pyrolysis product thus obtained has a composition roughly corresponding to the total formula NII4P03 and is in fact a mixture of ammonium polyphosphates. The product is rightly completely soluble in water, forming nearly neutral solutions (pil = 6-7). Such solutions do not result in precipitates with equivalent amounts of copper, zinc, manganese and iron salts (calculated assuming that the product corresponds to the formula NM4P03). In addition, such solutions dissolve those obtained in another way, especially precipitated deposits, for example, orthophosphates, hydroxides, oxides, carbonates of the above-mentioned metals in amounts similar to the equivalent ones. , carbonates, sulphates, chlorides, as well as borates and molybdenates in amounts corresponding to the requirements of a given plant constitute a convenient and effective microelement fertilizer. The urea phosphate pyrolysis product can also be dry mixed with the above-mentioned micronutrient materials and such mixtures can be used directly or dissolved in water. It is also possible to enrich these products with other fertilizing materials, especially with potassium salts, urea and ammonium nitrate. If the micronutrients are added to urea phosphate at the end of the pyrolysis process in the form of oxides, hydroxides or carbonates, they are obtained as a polyphosphate product of the metals concerned, and thus without ammonium salts EXAMPLE 1 1 kg of dry urea phosphate is pyrolyzed by heating to 200 ° C, yielding about 653 g of product with a composition approximately corresponding to the formula NH4PO3. The product is dissolved in 10 liters of water, and 825 g of pentahydrate copper sulphate is added to the obtained solution, after possible filtering off the amount of insoluble matter, to obtain a solution containing 8.6 g of nitrogen per liter, 43.8 g of phosphorus pentoxide and 20 g of complexed copper. . The solution is suitable, after appropriate dilution, as a micronutrient fertilizer and also as a plant protection agent used as spray or as an additive to liquid fertilizers. Example II. 1 kg of urea phosphate is pyrolysed by heating to 200 ° C, and after reaching this temperature, a finely powdered mixture of copper oxides or carbonates of copper, manganese, zinc and iron in a total amount of about 6 gram equivalents and in proportions corresponding to the composition is added while stirring. desired product. After thorough mixing and the emission of ammonia has ceased, the product is cooled down and possibly ground. The product can be optionally mixed with an appropriate amount of boric acid and sodium or ammonium molybdate. In this form, the product is suitable for the preparation of micronutrient solutions or as an additive to liquid fertilizers, especially nitrogen and nitrogen-phosphorus fertilizers. Patent disclaimer A method of producing micronutrient fertilizers in a complex form , characterized in that the complexing agent is the pyrolysis product of urea phosphate by heating it to a temperature of 140-220 ° C, the microelements in the form of oxides or hydroxides or salts are added to urea phosphate during its pyrolysis or the finished pyrolysis product possibly to a solution of the aqueous pyrolysis product. Pracownia Poligraficzna UP PRL. Mintage 120 copies Price PLN 100 PL

Claims (1)

Claim 1. A method of producing micronutrient fertilizers in a complexed form, characterized in that the complexing agent is the pyrolysis product of urea phosphate by heating it to a temperature of 140-220 ° C, the micronutrients in the form of oxides or hydroxides or salts are added to urea phosphate during its pyrolysis or to the finished pyrolysis product, or to a solution of the aqueous pyrolysis product. Printing workshop of the UP PRL. Mintage 120 copies Price PLN 100 PL